Dipper trip



P. S. STEVENS DIPPER TRIP March 2 1926.

Filed Nov. 21, 1925 A TTORNEY Patented Mar. 2, 1926.

units STATES I I 1,574,763 PATENT OFFICE.

PAUL $.BTEVENS, F S DUTH MILWAUKEE, WISCONSIN, ASSIGNOR 1'0 BUCYRUS COM- PANY, OF SOUTH MILWAUKEE, WISCONS-Tw.

DIPPER TRIP.

. y Application 'filed November 21, 1925. Serial'li'o. 70,565.

To all whom it may concern:

Be it known that I,PAUL 'S. STEVENS, a

citizen of the United States, and a resident a is provided with a bin I cations are introduced,

I tor, there of South Milwaukee,

particularly whiz and State of Wisconsin, have invented .cer-

tainnew and'useful Improvements in Dipper Trips, and I do hereby declare that the following is a full, clear, and exact description of said im rovements, such aswill enableothers skills in the art to which it appertains to make and use said invention. 7

This invention relates' to excavating machinery and more particularly to that type "of excavating machine commonly known? as a power shovel, the primary objectoi the invention being to provide novel means'for causing the bottom of the dipper of such shovel to be released for dumping the load,

In theusual construction of power shovels, the excavatin end of'a air 0 dipper-sticks, or handle, which is signed to reciprocate with respect to, a-nd' swing about, a certain point on the boom of the excavator. The dipper ed bottom, which is releasably held closed y means of a latch. mechanism.

In the-usual construction of a dipper trip, a rope extends from this latch to the t machine. In variations of this device,

the tripping, elaborate means have been devised to. compensate for. the reciprocating and swinging movements of "the dipperhandle. Such acomplicated device can be avoided, if a feasible means is found for mounting the tripping motor on the dipper-, handle itself. I

In an electrical excavator, where electricity is the only power available, new complidue to the employ ment of a rotating motor to supply the force for the, tripping.

on the mean platform, a light current must continuously pass through 1t, to take u the slack in the trip rope as the dipper-handle swings and reel rocates. This current tends to overheat an burn out the motor. l 1 And, re ardless of the location of the moas always been required an elaborate electrical mechanism to cut outthe current the instant that tripping has been county of Milwaukee,

the art, and thereforeneed, not be herein dipper is mounted on the ofite'ratorsposition on themain platform of npower is, employed to do held other adequate actuating means. In devices in which this motor 18 mounted accomplished Otherwise the motor will stall; and, unless special overload relays are provided to revent holding a high torque with full volage, this would burn out the motor. Furthermore the motor' will be brouht up to stalling with such a jar, that. the y-wheelenergy built up in the rotating armaturewill wear out the drum and ropes alrlidf chains, and will even bend the motors a t.

do away with these evils, by providing a rotating motor whichwill actuate a'dipper trip without the possibility of overheating or stalling, and without the need of elaborate control. v p

Other objects and advantages of my invention will 'be evident to. those skilled in more specifically set. forth.

and in the combinations and arrangementsdefined in the appended claim and of which one embodiment is exempli ed in-nthe accompanyin drawings, which are hereinafter particu arly described and explained.

Throughout, the same reference number-1i;

applied to the ame or similar members. v igure 'lisei side elevation of a dipper, di per-handl and some of the related parts 0 a power s iovel, showing my dipper trip mechanism in: place.

Figure 2 is an enlarged plan view of part of a dipper and its two. handles, with my di er trip in place. p

igure 3 is an; enlarged side elevation of the motor and related parts of my dipper trip mechanism shown in Figure 1. v

The dipper 1 has a swinging bottom 2 by the hinge 3. The bottom is held closed by the latch 4 which slides in guides 5 and engages a latch-keeper 6.

The latch may be induced to engage the latch-keeper by means gravity, or any secured at'the end of. I

9, mounted for rotation on theboomlO.

The rotation of these pinions by any suitable means (not in and out. cation Shown,

shown) thrnstthe In the particular the dipper and dipper It is one ofthe objects'ofm'y invention to he invention consists in the novel parts lification' shown, ed with racks 8 forengagement with shipper-shaft pinions etemplifi afeswungabout the ship er-shaft by means of 'appro riate flexible means, passes to, is

woun around, and is anchored to a drum 16, mounted in journals 17 -on the dipperhandle 7. On'one end of this drum 16, there is a lever 18, which is actuated by a connecting-rod 19, which extends to and.

is actuated by a. gear 2), journally mounted on one of the handles 7 The word drum," as used herein, is intended to mean any member, such as a drum or shaft, which performs the functions of a. drum. The

connecting-rod 19, although shown as one integral piece, may be made of parts permitting such'adjustment in the length of this unit as may be required; An appropriate leverage system may be substituted for the chain 15, shaft 16 and lever 18. The

connecting-rod 19 may be made flexible.

The gear 20 is'rotated by a pinion 21 mounted on the e ndIofthe shaft of an electric inotor 22. v

This motor is electrically connected to the power source by means of a flexible conductor23, a cable take-up box 24 of any appropriate design, a conductor 25 extend ingto the operators position, and a switch of any appropriate design (not shown) under the control of the o erator.

For the purposes of the ollowing geometrical explanation, I have lettered four points in Figure 3 as follows: ,A is the center of the wheel 20'; B is the point of connection of the. connecting-rod '19 and the wheel 2011C is the point of connection of the connectingrod 19'and the lever 18'; D is the center of rotation of the lever 18. g

The parts- 18, 19 and .120 are so proper, tioned and the points A aln'd D are so located that AB is appreciably essthan DC; and so that, if of BC and AD either one exceeds the other, the-difference )etWeen-them shall be appreciably less than eDC minus AB.-

lt will be readily seen that, when thedipper 1 has been hoisted and extended-to the proper position for dumping, the operator can 'trip the same by closingthe switch above referred to. The motor ,22

will then rotate, thus rotating the pinion 21 and the gear 20. The rotation of the gear. 20 will reciprocate the connecting-rod 19, thus oscillating the lever 18 back' and forth between its'two positions as shown inFig- .ure 3, and thus alternately winding up, and unwindingthe' chain 15 about the rod 16.

With each winding up of the chain 15, the latch 4 will be disengaged from the latchkeeper 6,- thus permitting the dipper bottom 2 to swing down erdin a clockwise direc:

dipper-handle, an excavating dipper on my invention has been shown, I do not intend to be limited thereto. It is within. the scope of my invention to employ other types of rotating motor than those actuated by electricity, and to employ other intermediate connections between-the latch and the motor than those shownland described, or suggested, herein.

Having now particularly described and 35 illustratedone form of my improved dipper trip, I claim r 1. n a dipper trip, the combination of a said handle, a dump-door to said dipper, a latch for said door, a latch-keeper'for said latch, a drum journally mounted in said handle, a chain to retract said latch from said latch-keeperand extending from said latch to said drum and wound about said drum, a lever to rotate said dr um, an electric motor mounted on said dipper-handle, a wheel rotated by. said motor, and it connect:

ing-rod connecting said wheel and said lever;

the radiusdistance from theipoint ofcom nection of the connecting-rod andwheelto the center of said wheel beingappreciably less than the radius "distance from the point of connection of the connecting-rod and lover to the center of rotation of said lever; and the difference between the length of the connecting-rod and the distance from the center of said wheel to the center of rota-v tion'of said lever bein appreciably less than the difference of s ai radii. V

1 2. In'a dipper trip, the combination oiv a dipper-handle, an excavating dipper on said handle, a dump door tosaid dipper, a latch for said door, a latch-keeper for said "latch, a' drum journal-11y mounted in said handle,

a chain to retract said. latch from said latclr keeper and associated with said latch and said drumfandwound about said drum, a.

lever to rotate said drum, an electric motor mounted on said dipper-handle, a wheel rotatedby said motor, and a connecting member. connecting 'sa'id* vlieel;-; and said length of the connecting memberii ggd; m

from'thecenter of said wheel to the tor ofarotation of said lever bein appreme less than the difference of said radii. s: 8. n a di per trip, the combination of a dipper-hand e, an eacavatin dipper on said I die, a dump-door to sai dipper, a" latch id! said .door, a drum journally mounted in 'said handle, a flexible member vto unlatch latch and associated with said latch and 'drum' and wound about said drum, a or to rotate said drum, a ower element mounted on said dipper-hand e, a wheel rou ted by said power element, and a connectng member connecting said wheel and said lever; .the radius distance from the point of eonnection of the connecting member and Wheel to the center of said wheel being apecigblyless than the radius distance from t of connection of the connecting 'r and lever to the center ofrotation 6! said lever; and. the difference between the of the connecting member and the nil cejfiom the center of said wheel to Tithe center of rotation of said lever being ap reciably less than the difference of said I 4. In a di per trip, the combination of an excavating ipper, a dump-door to said dipper, a latch for said door, a drum journa-lly 80 mounted in fixed relation to said dipper; a'

-flexi'blemember to unlatch said late and associated with said latch and said drum and wound about said drum, a lever to rotate said drum, an electric motor mounted in fixed relation to said dipper, a wheel rotated by said motor, and connecting means connecting said ,wheel and said lever; the radius disttmcefrom the point of connection of the conne'ctin means and wheel to the center of and whee being appreciably less than the radius distance from the point of connection of the connecting means and lever to the center ofrotation of said lever; and the difference between the length of the connecting means and the distance from the center of said wheel to the center of rotation of said lever being appreciably less than the difference of said radii;

5. In a di per trip, the combination of an excavating ipper, a dump-door to said dip per, a latch for said door, a drum journally mounted in fixed relation to said dipper, a flexible member to unlatch said latch and associated with said latch and said drum and wound about said drum, a lever to rot ate said drum, a motor mounted in fixed relation tosaid dipper, a wheel rotated by said motor, and connecting means connecting said wheel and said lever; said connecting means, wheel and lover being so proportioned and dis.- posed that a complete rotation of said wheel oscillates's'aid lever through merely a certain predetermined are. I

6. In a dipper trip, the combination of a dipper-handle, an excavating dippi r on said handle, a dump-door to said dipper, a latch for said door, a lever mounted on said handle, means to unlatch said latch. and

of rotation of said lever; and the difference between the length of theconneeting means and the distance from the center of said wheel to the center of rotation of said lever being a preciably less than the diiference ot said ra i1.

- 7. In a dip er trip, the combination of an excavating ipper, a dump-door to said dipper, aiatch for said door,a lever mounted on a pivot which bears a fixed relation to said dipper, means to unlatch said latch and associatedwith said latch and said lever,

an electric motor mounted in fixed relation to said dipper, a wheel rotated by said motor, and connecting means connecting said wheel and said lever; the radius distance from the point of connection of the connectmeans and wheel to the center of said in wEeel being up reciablyless than the radius distance from t e point of connection of the connecting means and lever to the center of rotation of said lever; and the difference between the length ofithe connecting means and the distance from the center of said Wheel to the center of rotation of said lever being appreciably less than the difference of said radii.

8. In a dipper trip, the combination of an excavating dipper, a dump-door to said dipper, a latch for said door, a lever mounted on a pivot which bears a fixed-relation'to said dipper, means to unlatc'h said latch and associated with said latch and said lever, a motor mounted in fixed relation to ,said dipper, a wheel rotated by said motor, and a connecting-rod connecting said wheel and said lever; said connecting-1'od, wheel and lover being so proportioned .and disposed that a complete rotation of said wheel oscil:

lates said lever through merely a certain predetermined arc.

9. In a dipper trip, the combination of an excavating dipper, a. dump-door to said dip per, a latch forsaid door, a lever mounted on a pivot which bears a fixed relation to said dipper, means to unlatch said latch and associated with said latch and said lever, in motor mounted in fixed relation to said dipper, a wheel'rotated by said motor, and connecting means connecting said wheel and said lever; said connecting means, wheel and lever being so proportionedanddisposed that a complete rotation of said \vheel oscillates said lever through merely a certain predetermined arc.

1Q. ,In a" 'dippertrip, the combinationbf an excavating, dipper, a dump-door to said dippeiga latch forsaid door, a'latch-keeper for said latch, means to retract said latch from said latch-l-:eeper, a motor mounted in fixed rel'ationto said dipper, a wheel rotated by said motor, and actuating said means; said Wheel and said means being so i proportioned and disposed that a complete rotation of said wheel merely retracts said latch a predetermined distance.

1.1; In a dipper trip, the combination of an excavating dipper, a dump-door "to said dipper, a latch for said door, means to unlatch said latch, a motor mountedin fixed relation'to said dipper, a wheel rotated by said motor, and actuating said means; said :wheel and said means beingiso proportioned and disposed that a complete 'rotation of said Wheel actuates said latch not appreciably more than enough to unlatch it.'-

12. ha dipper trip, the combination of an excavating dipper, a dump-doorto Said dipper, a latch for said door, means to un latch said latch, a motor mountedin fixed relation to said dipper, a Wheel rotated by said motor, and actuating saidmeans; said wheel and said means being so roportioned and disposed that said wheel is ree to rotate continuously and that rotation of said Wheel merely'retracts said latch a predeterfmined distance.

PAUL s. STEVENS; 

